Mid-boom sheeting

Submitted by Bob41 on Sun, 05/30/2004 - 10:28

For those of you interested in converting your mainsheet to the mid-boom location Harry has instructions and photos on the Flying Scot web page. Click on "How to" found on the left side of the web page menu. Thanks Harry.

Comments

Bob,
Great solution for the Scot mainsheet fouling scenario, should work well, although you lose a little purchase due to leverage, but for cruising with a motor on the bracket it would be fine. I can suggest one KEY thing to remember... unwanted or uncontrolled gybes can lead to boom breakage, as you have about 6.5 feet of unsupported boom and sail banging over and taking up on a load midpoint. Don't ask me how I know the ramifications of this happening...(chuckle).

Barry,
I am seriously considering a mid-boom sheeting solution to avoid the deck ape drill of hauling the motor aboard, and it sounds like you have some (ahem) "experience" with this rig. I am exploring an idea I read about in Scots & Water a few years back that sounded interesting: For moderate to heavy wind days, or just for some relaxed cruising, the FS can be rigged with a Snipe mainsail. Its smaller area eases the heeling and the forces on the boom. Sounds like a perfect cruising solution to avoid the reefing drill underway and the bunching of the main around your head. Comments?
If you don't know where you are going you gotta be careful, because you might not get there.
--Yogi Berra

Greystone, early efforts at mid-boom sheeting led to 2 conclusions- that the booms are weakened by additional drilling for the bails, and 6+ feet of boom with the large sail area aft of the final bail is a tremendous leverage point if an uncontrolled gybe is allowed. Secondly, reefing the large sail single-handed is a chore, leaving no mid-boom block if rolled, or a large amount of sail in the way if slab-reefed. I decided to go back to the original mainsheet plan, as I remove the motor after getting underway (I use a safety tether to the motor in case of droppage- lost one on another boat)and store it under the aft deck. I usually find that the motor is unnecessary as it's usually possible to sail away from most areas given the right conditions, and makes the delicate removal process moot.
As for the main, I found another Scot mainsail, measured the distance to the jib masthound from the boom, and had the sailfoot cut and the boltrope sewn in there and the loadpoints reinforced. A small wire pennant at the clew attaches to the outhaul. If I want a leisurely sail, or expect the winds to come up, I hoist the shortened main and sail on. I carry it rolled and stored under the port seat secured with bungees in case I get caught unaware or just want to relax. It's a little more time involved to drop the full main and get it off and rolled, then rig the shortened main, but once done is much better than dealing with a sheeting angle or folds in the way. Lately I've found I use the shortened sail more often than not, and the boat moves just as well with it, even in light air. Not as fast, of course, but just as maneuverable and less work. A Snipe or other mains'l would work also. I have found it to be an excellent addition to the sail inventory.
For clarification, my modifications included a 1/4" through-bolt to secure the bail, where the Flying Scot kit uses 4 3/16" rivets. I'm sure after looking at the Scot kit that Harry has designed it to work without any detriment to the rig. Unexpected gybes of sudden and severe nature are always scary, though, and can lead to damage on any boat.

quote:[i]Originally posted by Bob41[/i]
[br]For those of you interested in converting your mainsheet to the mid-boom location Harry has instructions and photos on the Flying Scot web page. Click on "How to" found on the left side of the web page menu. Thanks Harry.

Does the extra bail in the new midboom mainsheet purchase hardware kit from FS Inc really signficantly weaken the boom? It seems like a great idea but if genuinely degrades the boom strength... I'd love to hear Harry's take on this directly.

Yesterday I sailed with my new mid-boom rigging for the first time. I love how compact it is and easy to use. It was also a relief to leave the motor on the bracket and sail until the last gasp of wind was gone. We were in mild conditions and didn't exceed six knots.
Converting cost me about 15.00 in parts and I needed my cordless drill, one screwdriver, and my rivet gun. You can re-use two of the screws in the centerboard cap but they won't sit flat on the new eyestrap if they're cupheads. It looked more bristol to use four new flatheads.
You can generate quite a debate about the holes drilled for rivets in the boom. One school claims it weakens it and another that the rivets make up for lost material if installed correctly. Pick your opinion and try to prove it.
It did seem to me that the boom did a fair amount of flexing when the wind picked up. I thought that a stronger more touring oriented boom might make sense for those of us unconcerned about what is "legal" for the Scot. I'd like to know what Harry thinks of that. I want to stick with this neater configuration and if replacing the boom would help make that more practical I would find that a okay tradeoff.
Lets hear from others who have tried this.

Regarding the strength of the boom in the midboom sheeting arrangement... I wonder if there is a way to reinforce the boom. Perhaps (for example) adding re-inforcement bars to its sides, would provide enough extra strength to avoid having to replace it with a new, sturdier boom. Anyone have thoughts about this possibility?
Joe C.

I tried the new mid-boom purchase mainsheet rigging this past week, and (like Bob) I was very happy with it. The mainsheet tackle is all concentrated in one area - it's very neat and tidy. It allowed us to leave the motor on the bracket with no chance of fouling; my daughter and a friend were diving off the stern into the lake and there were absolutely no lines to trip over, or get in the way.
The winds were light so I had no chance of observing boom flex, but I think that unless winds are are especially gusty (or I'm racing), I will use the new arrangment. Thanks Harry for a super solution! The parts in the kit from Flying Scot were a snap to install.

There is no doubt that putting the mainsheet purchase in the middle of the boom puts a lot more load on the boom and that the extra bail in center does weaken the boom. You should not expect to sail the boat as aggressively with it rigged this way as you do with it rigged to the end of the boom. Don't do uncontrolled gybes or sheet in hard going upwind when it blows over 15.
This rig is a good way to keep the mainsheet away from the motor while sailing with the motor on the transom. For most, the advantage of not dealing with removing and installing the motor is worth a little sacrifice in performance.

Has anyone tried the alternate method of end boom sheeting that FS suggested a couple of years ago? It involved drilling two holes a few inches in from the stern and an inch or so in from either side and running a line through each hole. The main sheet block was then moved off the rudder and attached to the center of this line. It looked interesting but I am reluctant to drill holes in the deck for a system that may not be any better that the original one.

FWIW - the conversion took all of about 10 minutes to complete AND can be reversed in about the same amount of time. While it isn't clear in the instructions, this is a great option for those wanting to maintain safe motor use AND continue to race. I love it!
Brian
Update: This is a great way to cruise or light race a scot. The kids love it and it makes the boat really simple for anyone to sail. It was like a whole new boat.